The opening act on Thursday evening was the setting of Jupiter and Venus behind Bristol Head. The separation between these two planets is slowly decreasing toward a close conjunction on 08 June.
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| Jupiter (L) and Venus (R). Vivitar Series 1 90mm f/2.5 |
Near the end of astronomical twilight, the giant globular cluster Omega Centauri can be seen skimming the southern horizon.
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| Omega Centauri over Piedra Peak. Vivitar S1 90mm |
A wider view taken about 40 minutes later shows just how low the cluster is in the sky:
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| Omega Centauri (circled). OM 20mm f/1.4 + sparkle-6 filter |
This wider view also reveals layers of colorful airglow. The measured sky brightness directly overhead was sqml=21.51 mpsas, which is a good but not great value. Airglow is the likely explanation for this brighter sky, compared to measurements in mid-May, which were near 21.8. The airglow really stands out in pictures of the rising Milky Way.
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| Scorpius and Milky Way rising above Snowshoe Mountain. OM 20mm + softon |
The airglow presents as moving ripples of color in the sky, visible to the camera but not to the eye.



















